=== Happy Computer 8bit Printer Port upgrade (DIY) ===
A fine good method to upgrade to full 8bit has been described in the german magazine "Happy Computer Sonderheft 4/86": * Disconnect the D7 pin from ground, and wire it to the [[8255|PIO]]s Tape WR DATA pin instead (That is, Pin 12 of the 8255 chip).
Sharing that pin will cause no problems (as long as you do not attempt to send data to the tape drive and to printer at the same time). Of course, you will also have to customize your software, or BIOS ROM, or the BIOS jump vectors in RAM, in order to take advantage of the modification.